Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical review. B, Condensed matter

Solid-state masers without inversion: Theoretical prediction for high-efficiency oscillators or phase-sensitive detectors

F. F. Popescu

Published Nov 1, 1993• 9 citations
Publisher

Abstract

Analytic steady-state solutions of the density-matrix equation are derived by means of a formalism suitable for multilevel spin systems in dilute paramagnetic solids at high temperature and subjected to several strong fields. It is shown that solid-state masers without inversion may be obtained in the presence of one, two, or three quasimonochromatic strong fields at resonance. In the usual cases of two fields, the maser action with or without inversion cannot achieve high-efficiency microwave generation or detection, since for strong emitted fields, the saturating and nonlinear effects are strong too. On the contrary, whenever three frequency-correlated fields fulfill the ``spectroscopic bridge'' conditions, the saturating effects do not occur, and linear effects prevail, even when all these fields are strong. In this case, high-efficiency microwave generations or phase-sensitive detections may be achieved.

DOI
10.1103/physrevb.48.13569

Related papers

THE APPLICABILITY OF THE CAVES THEOREM TO SOLID-STATE MASERS WITHOUT INVERSION

Mihai Oane, Florin F. Popescu, Shyh‐Lin Tsao +4 more

The development of masers in the 1950s made possible amplifiers that were much quieter than other contemporary amplifiers. An analysis of narrow-band yields a fundamental theorem (Caves theorem) for phase-insensitive linear amplifiers; it requires that such an amplifier, will add noise as large as half-quantum of zero-point fluctuations. For phase-sensitive linear amplifiers the theorem establish a lower limit on the product of the noises added to the two phases. In the last decade it was shown theoretically that solid-state masers without inversion may be obtained in multilevel spin systems in dilute paramagnetic solids at high temperature subjected to several strong microwave fields. In the present paper the authors apply the Caves theorem to the maser without inversion in order to find out the best ways in which the proposed device can work.

•Jan 1, 2008•0 citations

Linear and nonsaturating effects in atomic multiplets subjected to three strong electromagnetic fields of resonance

F. F. Popescu, Florea Marica, Gabriel Lucian Radu

Analytic steady-state solutions of the density-matrix equation are discussed for multilevel spin systems in dilute paramagnetic solids at high temperature and subjected to three frequency- correlated fields at resonance. Unlike the double resonance, in the case of triple resonance, when the three microwave fields are sufficiently strong and the spectroscopic bridge conditions are satisfied, important linear and nonsaturating effects are predicted.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Jul 2, 1998•0 citations

Quantum limits on noise in solid state masters without inversion

Mihai Oane

The development of masers in the 1950's made possible amplifiers that were much quieter than other contemporary amplifiers. An analysis of narrow-band yields a fundamental theorem (Caves theorem) for phase-insensitive linear amplifiers; it requires that such an amplifier, will add noise as large as half-quantum of zero-point fluctuations. For phase-sensitive linear amplifiers the theorem establish a lower limit on the product of the noises added to the two phases. In the last decade it was shown theoretically that solid-state masers without inversion may be obtained in multilevel spin systems in dilute paramagnetic solids at high temperature subjected to several strong fields. In the present paper the author applies the Caves theorem to the maser without inversion in order to find out the best ways in which the proposed device can work.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Oct 21, 2004•0 citations

Theory of a type of quantum amplification: Phase-sensitive amplification by frequency upconversion

F. F. Popescu

It is shown that the spectroscopic bridge, a recently proposed method to achieve high-efficiency microwave oscillators and phase-sensitive detectors, may be used in a spin multiplet of certain paramagnetic ions to obtain a type of microwave quantum amplification: phase-sensitive amplification by frequency upconversion. This operation of a solid-state maser without population inversion is based on a principle similar to that used for achieving amplification in a transistor (triode). The major differences between this amplification and the parametric amplification, or the usual double-resonance maser action, are discussed.

Physical review. B, Condensed matter•Jun 15, 1995•5 citations

A Theory of Microwave Masers in Strong Pumping Field

Yoshio Ebina

Maser action due to a mixing between unperturbed spin states, which is produced by a strong coherent pumping field at an angular frequency ω, is investigated by using rate equations of a spin density matrix referred to a rotating coordinate system. The relaxation of each state, which was introduced usually by phenomenological considerations, is obtained from an interaction Hamiltonian of the spin moments with local fields. The induced oscillating fields at 2ω±ω s and ω s , which are proportional to a small signal field at a frequency ω s , have the possibility of power emission (or absorption) by choosing suitably the pumping field. The components at 2ω±ω s are responsible for a frequency mixing between ω and ω±ω s occuring in the rotating coordinates. The emitted (or absorbed) line shape is not a simple Lorentzian in the case of the spin moment \(1{\times}\hbar\) and considered to be a quantum affect in the three level scheme. The frequencies of the emitted (or absorbed) fields are expected to be shifted by varying the magnitude, or the frequency of the pumping field, or the static magnetic field.

Journal of the Physical Society of Japan•Nov 1, 1964•0 citations

Theory of a Three-Level Maser

Ali Javan

In a three-level maser, a transition between two energy levels is saturated in order to produce an induced emission of power at a lower frequency corresponding to a transition between an intermediate energy level and one or the other of the two saturated levels. In this paper, certain effects are discussed which cannot be predicted from a theory in which the population differences alone are considered in this process. For instance, it is shown that, in some cases it is possible to obtain for the same system an induced emission of power at two frequencies given by the resonances between the intermediate energy level and both of the saturated levels. Also, it is shown that, even in the absence of inhomogeneous broadening of the spectral line, one can obtain a net induced emission at some portions of a resonant line and a net absorption at other frequencies within the line widths. Such effects become important even in early stages of saturation in cases where ${T}_{1}={T}_{2}$ which is true for ordinary gaseous systems and individual spin systems in a majority of very dilute paramagnetic solids. A complete theory is discussed for a gaseous system and extended to two limiting cases of paramagnetic materials with ${T}_{1}={T}_{2}$ and ${T}_{2}\ensuremath{\ll}{T}_{1}$ for each individual spin system. Furthermore, it is shown that for a saturating field of fixed frequency, the integral of induced power over the entire line is in full agreement with the results of a semiclassical treatment in which the population differences alone are considered. Some remarks are made as to the practicability of certain systems of this type.

Physical Review•Sep 15, 1957•258 citations
Analytic steady-state solutions of the density-matrix equation are derived by means of a formalism suitable for multilevel spin systems in dilute paramagnetic solids at high temperature and subjected to several strong fields. It is shown that solid-state masers without inversion may be obtained in the presence of one, two, or three quasimonochromatic strong fields at resonance. In the usual cases of two fields, the maser action with or without inversion cannot achieve high-efficiency microwave generation or detection, since for strong emitted fields, the saturating and nonlinear effects are strong too. On the contrary, whenever three frequency-correlated fields fulfill the ``spectroscopic bridge'' conditions, the saturating effects do not occur, and linear effects prevail, even when all these fields are strong. In this case, high-efficiency microwave generations or phase-sensitive detections may be achieved.
The development of masers in the 1950s made possible amplifiers that were much quieter than other contemporary amplifiers. An analysis of narrow-band yields a fundamental theorem (Caves theorem) for phase-insensitive linear amplifiers; it requires that such an amplifier, will add noise as large as half-quantum of zero-point fluctuations. For phase-sensitive linear amplifiers the theorem establish a lower limit on the product of the noises added to the two phases. In the last decade it was shown theoretically that solid-state masers without inversion may be obtained in multilevel spin systems in dilute paramagnetic solids at high temperature subjected to several strong microwave fields. In the present paper the authors apply the Caves theorem to the maser without inversion in order to find out the best ways in which the proposed device can work.
The development of masers in the 1950's made possible amplifiers that were much quieter than other contemporary amplifiers. An analysis of narrow-band yields a fundamental theorem (Caves theorem) for phase-insensitive linear amplifiers; it requires that such an amplifier, will add noise as large as half-quantum of zero-point fluctuations. For phase-sensitive linear amplifiers the theorem establish a lower limit on the product of the noises added to the two phases. In the last decade it was shown theoretically that solid-state masers without inversion may be obtained in multilevel spin systems in dilute paramagnetic solids at high temperature subjected to several strong fields. In the present paper the author applies the Caves theorem to the maser without inversion in order to find out the best ways in which the proposed device can work.
It is shown that the spectroscopic bridge, a recently proposed method to achieve high-efficiency microwave oscillators and phase-sensitive detectors, may be used in a spin multiplet of certain paramagnetic ions to obtain a type of microwave quantum amplification: phase-sensitive amplification by frequency upconversion. This operation of a solid-state maser without population inversion is based on a principle similar to that used for achieving amplification in a transistor (triode). The major differences between this amplification and the parametric amplification, or the usual double-resonance maser action, are discussed.
Maser action due to a mixing between unperturbed spin states, which is produced by a strong coherent pumping field at an angular frequency ω, is investigated by using rate equations of a spin density matrix referred to a rotating coordinate system. The relaxation of each state, which was introduced usually by phenomenological considerations, is obtained from an interaction Hamiltonian of the spin moments with local fields. The induced oscillating fields at 2ω±ω s and ω s , which are proportional to a small signal field at a frequency ω s , have the possibility of power emission (or absorption) by choosing suitably the pumping field. The components at 2ω±ω s are responsible for a frequency mixing between ω and ω±ω s occuring in the rotating coordinates. The emitted (or absorbed) line shape is not a simple Lorentzian in the case of the spin moment 1×ℏ1{\times}\hbar1×ℏ and considered to be a quantum affect in the three level scheme. The frequencies of the emitted (or absorbed) fields are expected to be shifted by varying the magnitude, or the frequency of the pumping field, or the static magnetic field.
In a three-level maser, a transition between two energy levels is saturated in order to produce an induced emission of power at a lower frequency corresponding to a transition between an intermediate energy level and one or the other of the two saturated levels. In this paper, certain effects are discussed which cannot be predicted from a theory in which the population differences alone are considered in this process. For instance, it is shown that, in some cases it is possible to obtain for the same system an induced emission of power at two frequencies given by the resonances between the intermediate energy level and both of the saturated levels. Also, it is shown that, even in the absence of inhomogeneous broadening of the spectral line, one can obtain a net induced emission at some portions of a resonant line and a net absorption at other frequencies within the line widths. Such effects become important even in early stages of saturation in cases where T1=T2{T}_{1}={T}_{2}T1​=T2​ which is true for ordinary gaseous systems and individual spin systems in a majority of very dilute paramagnetic solids. A complete theory is discussed for a gaseous system and extended to two limiting cases of paramagnetic materials with T1=T2{T}_{1}={T}_{2}T1​=T2​ and ${T}_{2}\ensuremath{\ll}{T}_{1}$ for each individual spin system. Furthermore, it is shown that for a saturating field of fixed frequency, the integral of induced power over the entire line is in full agreement with the results of a semiclassical treatment in which the population differences alone are considered. Some remarks are made as to the practicability of certain systems of this type.